The present disclosure relates to an interface structure using spring contacts, particularly to the interface structure for detachably connecting an electronic component such as an IC socket to a board.
IC sockets have been widely used as an interface for electrically connecting a semiconductor device to a print board. An IC socket loading a surface-mount type semiconductor device such as BGA (Ball Grid Array), CSP (Chip Sized Package) or LGA (Land Grid Array) includes a base member on which the bottom surface of the semiconductor device is loaded, and a cover member that presses the loaded semiconductor device to the base member so as to allow solder balls at the bottom of the semiconductor device to contact with probe pins [See, for example, Japanese Patent publication no. 2001-093634A.
The IC socket is also mounted on a circuit board for measuring electrical characteristics or reliability of the loaded semiconductor device. In such mounting, since the terminals of the socket and the circuit board are directly connected each other by the solder, the socket cannot be easily removed from the board. Correspondingly, Japanese Patent No. 4854612B provides an adapter for socket for allowing the socket to be removed from the board. FIGS. 1, 2A and 2B are from Japanese Patent No. 4854612B and show an adaptor 10 for a socket 20. The adaptor 10 is connected in between a circuit board and the socket 20 to provide the electrical interface to both. The socket 20 enables to load different packages 1 such as BGA, LGA and LGA. The socket 20 includes, for example, a base member 30, a cover member 40 that reciprocates in directions approaching to or separating away from the base member 30, and a plurality of contacts 50 planted in the base member 30 respectively. The package 1 is loaded onto a mounting member through an opening 42 of the cover member 40. A pair of latch members 44 can be moved in response to the reciprocated movement of the cover member 40 and is rotated on a pin or rotation axis 46 to press the top surface of the package 1. The contacts 50 are supported by a contact support portion 34. The upper ends of the contacts 50 are contacted with the terminals at the bottom of the package 1 respectively. The lower ends of the contacts 50 are protruded from the base member 30 and are inserted into through holes of the adapter 10 respectively. Cylindrical post portions 36 used for positioning are formed at each corner portion of the bottom of the base member 30.
The adaptor 10 includes a main adaptor 12 which includes a lower adaptor 12a and an upper adaptor 12b. A plurality of through holes 14 are formed in the lower adaptor 12a and the upper adaptor 12b respectively, whose positions correspond to each contact 50. Additional through holes 64 for positioning are also formed in each corner portion of the main adaptor 12 to insert the post portion 36 of the socket 20. A probe pin 60 and a coil spring 62 for urging the probe pin 60 are accommodated in the through hole 14, and the probe pin 60 holds the contact inserted from the through hole 14.
FIG. 3 is also from Japanese Patent No. 4854612B and shows an enlarged cross sectional view with the probe pin 60 built in the through hole 14 of the main adaptor 12. The upper adaptor 12b is fixed on the upper surface of the lower adaptor 12a by hooks (now shown), and the probe pin 60 is held in the through hole 14. The contact 50 is held by a clip portion 68 of the probe pin 60 through an upper opening 14b. The lower end of the probe pin 60 is protruded from a lower opening 14B to contact with an electrode pad of the circuit board.